20636649839 has 8 divisors (see below), whose sum is σ = 22243996320. Its totient is φ = 19032147936.

The previous prime is 20636649829. The next prime is 20636649853. The reversal of 20636649839 is 93894663602.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20636649839 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20636649829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 696059 + ... + 725100.

It is an arithmetic number, because the mean of its divisors is an integer number (2780499540).

Almost surely, 2^20636649839 is an apocalyptic number.

20636649839 is a deficient number, since it is larger than the sum of its proper divisors (1607346481).

20636649839 is a wasteful number, since it uses less digits than its factorization.

20636649839 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1422289.

The product of its (nonzero) digits is 10077696, while the sum is 56.

The spelling of 20636649839 in words is "twenty billion, six hundred thirty-six million, six hundred forty-nine thousand, eight hundred thirty-nine".